For a displacement hull as on the Wellington with a 50' waterline, the theoretical hull speed is the square root of the waterline X 1.3, or 9.19 knots. Actually the horsepower required to produce hull speed in a displacement vessel is quite small since there is very little resistance until hull speed is reached. There are ways to calculate the required HP to produce hull speed and they are beyond the scope of my knowledge. Theoretical hull speed is just that and can vary somewhat. I once owned a 30 Willard Vega motorsailer that would produce 6 knots at 1200 RPM with a 50hp Perkins diesel. The developed horsepower at that throttle setting is about 15 or 16 shaft horsepower, so the 65 Wellington can easily achieve hull speed at a modest and economical throttle setting, using only a fraction of the available horsepower. The rest is available for tougher weather conditions when added power can keep you going against wind and current. My 2c worth.
To answer your question about speed, yes 160 hp turbo - 10+ knots and I did a sea trial and received the same values and tracked and charted the boat as it came from Anacortes, and it was a steady 8-10 knots on every leg.
--- In electricboats@yahoogroups.com, GNHBus@... wrote:
>
> A 160hp Diesel propels a 68000 lb vessel at 10 knots ????
>
>
> In a message dated 1/10/2011 2:57:52 P.M. Eastern Standard Time,> james@... writes:> _http://www.mastervolt.com/marine/products/hybridmaster/hybridmaster-96/_
>
>
>
>
> Master volt has a hybrid add on that can be added to any engine, that
> might be what your looking for.
> (http://www.mastervolt.com/marine/products/hybridmaster/hybridmaster-96/)>> html_
> Out side of that the highest hp electric motor that runs at safe 48 volts
> is the Electric yacht 360i.
> _http://www.electricyacht.com/electric-yacht-products/electric-yacht-system.
> (http://www.electricyacht.com/electric-yacht-products/electric-yacht-system.html)>
>
> There are a lot of "system" diagrams on Mastervolts site for different
> types of yachts.
> They seem to recommend dual pods for your size vessel.
>
>
> Good luck and ignore the wave of negative emails that are about to come
> your way.
>
>> On Jan 8, 2011, at 10:46 PM, "ibles_world" <ibles_world@...> wrote:> 2&ybw=&units=Feet¤cy=USD&access=Public&listing_id=60410&url=_
>
>
>
>
>
>
> I purchased a 65ft Motor Sailor, Wellington Design, details can be found
> here
>
> _http://www.yachtworld.com/core/listing/boatMergedDetails.jsp?boat_id=179705
> (http://www.yachtworld.com/core/listing/boatMergedDetails.jsp?boat_id=1797052&ybw=&u
> nits=Feet¤cy=USD&access=Public&listing_id=60410&url=)
>
> I would like to re-power this craft with a diesel electric in-board
> system, I plan on taking the boat for extended cruising, I am budgeting 30k for
> this modification, I would like to do it for less but if it cost more I
> fully understand that this is a boatt = Bust Out Another Ten Thousand.
>
> It is Powered by a 160hp Lehman turbo diesel engine presently (Running
> well), 15' beam, 68000lbs displacement (With the current power plant) it
> drafts at 6' with cruising gear, it has a Northern Lights 12.5kw generator Will
> upgrade if I have to. Hydraulic pto generator uninstaller but will be
> reinstalled, 1000 Gallon Diesel fuel tank, the solar panels are too old and
> worthless to contribute any notable power. plan on replacing them with better
> larger flat panels
>
> The Boat does 10 knots on average and I would like a bit more if it wont
> matter too much. The boat has a walk around engine room, so space in not an
> object. The current prop in a 3 blade variable pitch that I will be keeping.
>
> There is much I probable left out of this post, so please ask.
>
> Thank you
>
> Nicholas
> Ible's World
>
--
George Johnson
GeoMar Logistics
Jomtien, Chonburi
Thailand
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